Exhaust Gasket - Front

Replace the exhaust manifold gaskets on the 302ci V8 engine to eliminate exhaust leaks at the cylinder heads.

Warnings

Tools required

Parts

• Exhaust manifold gasket set (both sides) × 1 — Use OEM specification or Fel-Pro MS90026
• Exhaust manifold bolts (if corroded) × 16 — 5/16"-18 x 1.5" grade 8

Preparation

1. Park vehicle on level surface and allow engine and exhaust to cool completely (minimum 2 hours)
2. Disconnect negative battery cable
3. Raise front of vehicle and support securely on jackstands if additional clearance is needed for exhaust pipe removal
4. Apply penetrating oil to all visible exhaust manifold bolts and exhaust pipe flange nuts, allow to soak for 15-30 minutes

Procedure

1. 1

   Remove air cleaner assembly
   Remove the wing nut securing the air cleaner lid and remove the lid and air filter element. Remove the air cleaner base by loosening the hold-down bolt at the carburetor. Disconnect any vacuum hoses or crankcase breather hoses attached to the air cleaner base and set the assembly aside.
2. 2

   Disconnect exhaust pipes from manifolds
   Working from underneath the vehicle, locate the exhaust pipe flange connections at both exhaust manifolds. Remove the two nuts securing each exhaust pipe to its manifold flange. You may need to support the exhaust pipes with wire or a jack to prevent them from hanging on the remaining fasteners. If the studs turn with the nuts, use a 6-point socket and apply additional penetrating oil.
3. 3

   Remove spark plug wires (passenger side)
   On the passenger side manifold, remove the spark plug wire clips or looms as necessary to provide access. Pull spark plug wires off cylinders 1, 2, 3, and 4 by grasping the boot (not the wire) and twisting while pulling. Route wires away from the manifold work area.
4. 4

   Remove passenger side manifold fasteners
   Remove the 8 exhaust manifold bolts from the passenger side manifold. Start from the center and work outward to avoid warping. The bolts thread into the cylinder head. Some bolts may be difficult to access and will require a universal joint and extension. Keep track of bolt locations as some may be different lengths.
5. 5

   Remove passenger side exhaust manifold
   Carefully remove the passenger side exhaust manifold by lifting it away from the cylinder head. The manifold may be stuck to the head due to carbon buildup. Tap gently with a rubber mallet if needed. Remove and discard the old gasket. Inspect the manifold for cracks, especially around the ports.
6. 6

   Remove spark plug wires and components (driver side)
   On the driver side, disconnect the spark plug wires from cylinders 5, 6, 7, and 8 in the same manner as the passenger side. If equipped with air injection system (smog pump), disconnect the air injection line at the manifold check valve. Remove the dipstick tube bracket bolt if it interferes with manifold removal.
7. 7

   Remove driver side manifold fasteners
   Remove the 8 exhaust manifold bolts from the driver side manifold using the same pattern as the passenger side. The rear-most bolts will be challenging to access and may require a combination of universal joint, short extension, and working from different angles.
8. 8

   Remove driver side exhaust manifold
   Carefully remove the driver side exhaust manifold. This side may require maneuvering around the steering components and frame rail. Remove and discard the old gasket.
9. 9

   Clean cylinder head mating surfaces
   Using a gasket scraper and wire brush, thoroughly clean the exhaust port surfaces on both cylinder heads. Remove all old gasket material, carbon deposits, and corrosion. The surface must be completely clean and flat for proper gasket sealing. Wipe clean with shop towels. Stuff clean rags into the exhaust ports temporarily to prevent debris from entering the cylinders.
10. 10

    Inspect and clean exhaust manifolds
    Clean the manifold mating surfaces thoroughly with a wire brush and scraper. Inspect both manifolds carefully for cracks, especially between ports and around bolt holes. Check manifold flatness by placing on a known flat surface. Replace any cracked or warped manifolds.
11. 11

    Install new gaskets and driver side manifold
    Remove the rags from the exhaust ports. Position the new gasket on the driver side cylinder head, aligning all port openings. The gasket may have alignment tabs or be directional. Position the driver side manifold over the gasket and start all 8 bolts by hand to ensure proper alignment. Tighten bolts in a spiral pattern from the center outward to 18-24 ft-lbs in two stages: first to 12 ft-lbs, then to final torque of 18-24 ft-lbs.
12. 12

    Install passenger side manifold
    Position the new gasket on the passenger side cylinder head. Install the passenger side manifold and start all 8 bolts by hand. Tighten using the same spiral pattern from center outward: first to 12 ft-lbs, then to final torque of 18-24 ft-lbs.
13. 13

    Reconnect exhaust pipes
    Position the exhaust pipe flanges to their respective manifolds. Install new exhaust flange gaskets if the old ones are damaged. Install and tighten the flange nuts evenly to secure the exhaust pipes. Ensure pipes are properly aligned and not under stress.
14. 14

    Reconnect accessories and components
    Reconnect the dipstick tube bracket bolt if it was removed. Reconnect any air injection lines to the manifolds. Reinstall spark plug wires to their correct cylinders in the proper firing order, ensuring each boot is fully seated on its spark plug.
15. 15

    Reinstall air cleaner and final checks
    Reinstall the air cleaner base to the carburetor and tighten the hold-down bolt. Reconnect any vacuum hoses and breather hoses. Install the air filter element and air cleaner lid. Reconnect the negative battery cable.

Reassembly

1. Torque all exhaust manifold bolts in a spiral pattern from center outward to ensure even clamping pressure and prevent gasket leaks
2. Ensure spark plug wires are routed away from hot exhaust manifolds to prevent wire damage

Verification

• Start the engine and allow it to reach operating temperature while listening for exhaust leaks at the manifold-to-head interface
• Inspect all manifold bolt areas visually for signs of exhaust gas escaping (soot stains or visible smoke)
• Check that all spark plug wires are properly seated and not contacting hot exhaust components
• Verify no exhaust leaks at the exhaust pipe flange connections

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